碳化硅复合封孔剂对等离子喷涂YSZ涂层高温抗氧化性能的影响

Effect of SiC-based composite sealing agent on high temperature oxidation resistant of plasma sprayed YSZ coatings

采用球磨法结合溶胶凝胶法制备了CeO_(2)含量不同的碳化硅复合封孔剂,分别考察了复合封孔粒子及封孔处理后涂层的微观组织、物相组成及高温性能。结果表明,CeO_(2)能够有效增强复合封孔粒子的高温稳定性。随CeO_(2)含量的增加,复合封孔粒子的高温稳定性增强。封孔处理后,YSZ涂层表面出现明显的带有微裂纹的封孔层,CeO_(2)含量对封孔层的形貌影响不明显。经1300℃高温氧化10 h后,经封孔处理涂层的重量变化率明显低于未经处理的涂层。随CeO_(2)含量增加,涂层的脱落程度和氧化增重率均降低,涂层的抗氧化性能提高。

SiC-based composite sealing agents with various CeO_(2)content were prepared by ball-milling method combined with sol-gel method.The microstructure,phase composition and high temperature performance of the sealing particles and the sealed coatings were investigated.CeO_(2)can effectively enhance the high temperature stability of sealing particles.With the increase of CeO_(2)content,the high temperature stability of sealing particles was enhanced.The sealing layer with micro-cracks was formed on the surface of YSZ coatings after sealing treatment.The CeO_(2)content had no obvious effect on the morphology of the hole sealing layer.The weight changing rate of the coating was much lower than that of the untreated coatings after the coatings were oxidized 10 h at a high temperature of 1300℃.With the increase of CeO_(2)content,the oxidation resistant of the coatings increased.